Configuration reference

The Federation Core reads all runtime configuration from environment variables. The reference below is the source-of-truth set from core/config/config.go and the shipping .env.example.

Server

Variable	Default	Notes
`SERVER_PORT`	`8080`	HTTP listen port.
`LOG_LEVEL`	`info`	`debug` / `info` / `warn` / `error`.

Database (PostgreSQL)

Variable	Default	Notes
`DB_HOST`	`localhost`
`DB_PORT`	`5432`	Note: docker-compose maps Postgres to host port 5433. When running the Federation Core on the host (not in Docker), set `DB_PORT=5433`.
`DB_USER`	`fedshield`
`DB_PASSWORD`	`fedshield_dev`	Change before production.
`DB_NAME`	`fedshield`

Cache (Redis)

Variable	Default	Notes
`REDIS_HOST`	`localhost`
`REDIS_PORT`	`6379`

Auth

Variable	Default	Notes
`PEER_AUTH_ENABLED`	`false`	Set to `true` before production. Default is for local development convenience; with auth disabled, any caller can impersonate any peer.

Scoring engine — general

Variable	Default	Notes
`SCHEMA_VALIDATION_STRICT`	`true`	Reject events that fail JSON Schema validation. Keep `true` in production.
`TIME_DECAY_HALF_LIFE_DAYS`	`30`	Event weight is halved every N days.

Scoring engine — peer-weighting (EigenTrust)

Variable	Default	Notes
`ENGINE_EIGENTRUST_ALPHA`	`0.15`	Teleport probability. 0.15 matches the EigenTrust paper and PageRank’s damping factor.
`ENGINE_EIGENTRUST_MAX_ITER`	`50`	Iteration cap (protects the score-query latency budget).
`ENGINE_EIGENTRUST_EPSILON`	`1e-6`	Convergence threshold on max element delta between iterations.
`ENGINE_LOW_TRUST_CUTOFF`	`0.2`	Peers below this `P_t` are excluded from the aggregate. Calibration note: a three-peer collusion scenario (one honest, two adversaries) needs this lowered to `0.05` so the honest peer’s voice isn’t zeroed; see RESULTS.md.

Scoring engine — pre-trust seeds (gate G5)

Opt-in. With ENGINE_PRE_TRUST_ENABLED=false (default) the engine behaviour is bit-identical to the pre-G5 implementation. Pre-trusted peers have their P_t floored at ENGINE_PRE_TRUST_FLOOR and are exempt from the low-trust cutoff.

Variable	Default	Notes
`ENGINE_PRE_TRUST_ENABLED`	`false`
`ENGINE_PRE_TRUST_PEERS`	empty	Comma-separated peer IDs, e.g. `peer-a-uuid,peer-d-uuid`.
`ENGINE_PRE_TRUST_FLOOR`	`0.05`	Minimum `P_t` for pre-trusted peers.

Scoring engine — coordination detector (gate G5)

Opt-in. With ENGINE_COORDINATION_ENABLED=false (default) the cluster detector returns nil and ApplyClusterCap is a no-op.

Variable	Default	Notes
`ENGINE_COORDINATION_ENABLED`	`false`
`ENGINE_COORDINATION_MIN_EVENTS`	`10`	Per-peer minimum event count before the detector evaluates them. Below this, sampling variance dominates JSD.
`ENGINE_COORDINATION_SEVERITY_JSD`	`0.15`	Max JSD on severity distributions to cluster.
`ENGINE_COORDINATION_INTER_ARRIVAL_JSD`	`0.20`	Max JSD on inter-arrival distributions to cluster.
`ENGINE_COORDINATION_INFLUENCE_CAP`	`0.5`	Multiplier on clustered peers’ `P_t`. Calibration note: the three-peer minimum-honest-majority case needs this tightened to `0.1` so the honest peer can dominate the aggregate.

Recommended production defaults

For a federation with two bootstrap peers and active gate-G5 defence:

PEER_AUTH_ENABLED=true
SCHEMA_VALIDATION_STRICT=true

ENGINE_LOW_TRUST_CUTOFF=0.05
ENGINE_PRE_TRUST_ENABLED=true
ENGINE_PRE_TRUST_PEERS=peer-a-uuid,peer-d-uuid
ENGINE_PRE_TRUST_FLOOR=0.05

ENGINE_COORDINATION_ENABLED=true
ENGINE_COORDINATION_INFLUENCE_CAP=0.1

The other defaults are sensible. Tune the EigenTrust parameters only if you have a specific reason; they are well-calibrated for the prototype’s scale (a few to a few dozen peers).